Nonvolatile memory device having resistive memory cells including at least one resistive memory cell initial state

A nonvolatile memory device, comprising:

• a plurality of resistive memory cells each of which takes either a variable state or an initial state, the plurality of resistive memory cells including a memory group including at least one resistive memory cell in the initial state;
• and
• a read circuit comprising a resistance detection circuit that obtains resistance value information of the plurality of resistive memory cells, and a data generation circuit that generates digital data corresponding to the resistance value information obtained by the resistance detection circuit, wherein
• the resistance detection circuit comprises a voltage application circuit that selectively applies a first read voltage for reading a resistive memory cell in the variable state, and a second read voltage that is larger than the first read voltage and smaller than a voltage of a forming pulse that is an electrical stress for changing from the initial state to the variable state, and
• in order to obtain resistance value information of the at least one resistive memory cell in the initial state, the voltage application circuit applies the second read voltage to the at least one resistive memory cell in the initial state, and after the second read voltage is applied to the at least one resistive memory cell in the initial state, the at least one resistive memory cell maintains the initial state.